Drill-socket.



P. G. BLOMBERG.

DRILL SOGKET., APPLICATION IILED JUNE 4, 1910.

Patented Apr. 4, 1911.

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UNITED STA ES PER GOTTHARD BLOMBEBG, OF LILJEHOLME N, NEAR STOCKHOLM,SWEDEN, ASSIGNOR TO THE FIRM OF MEYER & KLEIN, F HAGEN, I. W. GERMANY.

DRILL-SOCKET.

Specification of Letters Patent.

Patented Apr. 1, 1911.

Application filed June 4, 1910. Serial No. 564,983.

To all whom it may concern:

Be it known that I, PER Gorrrrnno BLOM- nnne, a subject of the King ofSweden, and resident of Liljeholmen, near Stockholm, Sweden, haveinvented certain new and useful Improvements in Drill-Sockets, of whichthe following is a specification.

The present invention relates to a drill socket or chuck of the kindcomprising two rotatably connected members, and gripping jaws pivoted toone of said members and rovided with studs guided in radiating slots inthe other member, so that a rotary displacement effects a turning of thejaws about their pivots for increasing or diminishing the space betweenthe gripping surfaces, the members being connected by a spring tendingto hold the jaws in closed position.

The object of the invention is to simplify the manufacture of chucks ofthis kind, and for that purpose, the jaws, which are formed with an allthrough uniform cross-section, are adapted to roll along a cylindricalsurface and to bear against said surface when gripping, the pivots beingintended only to maintain the jaws in their proper position relative toeach other and therefore fitted in the same so as to allow a certainamount of free play. From this arrangement it follows that theconstruction of the chuck is greatly facilitated, since the tapping ofthe jaws for the reception of the pivots need not be done with any greataccuracy. Moreover, the turning of the cylindrical surface is a simpleoperation, and the jaws, which must be of equal shape, can simply becutout of an evenly rolled bar.

In the accompanying drawings are illustrated two forms of constructionof my improved drill socket and like letters of reference refer to likeparts throughout the various views.

Figure 1 shows a longitudinal cross-section of the drill socket, Fig. 2,a horizontal cross-section of Fig. 1, and Figs. 3 and 4:, a modificationof the construction shown in Figs. 1 and 2.

According to Figs. 1 and 2 the pins 5, on which the jaws r are looselymounted, are fastened with their ends in two rings 2 and 6. Said ringsare rotatably mounted in the casing 1. A spring 3, connected with oneend to the casing 1 and with the other end to the ring 2, tends to turnthe parts 2, 5,

6, in such a direction that the jaws close around the drill. In order toeasily turn said partsin the opposite direction, the ring 6 is formed inthe shape of a cap overlapping the top ends of the casing 1. The jaws 4must roll on the cylindrically turned inner face of the casing and arenot permitted to glide. In order to securely prevent the gliding eachjaw is provided with a pin 10 gliding in a radial groove of a slot 9. Inthe illustrated construction said grooves are arranged in a ring 8 fixedto the mouth of the casing 1 by means of screws 11.

The construction shown in Figs. 3 and 1 differs from the one abovedescribed in that the pins are connected to the fixed part of thesocket. The side wall of the casing is freely mounted and form arotatable shell 12 on the fixed part of the socket. The shell 12 isconnected with the spring 3 and is provided with grooves or slots forthe pins of the jaws. By this the ring 8 as well as the ring 2 becomessuperfluous and the rotatable cover can be replaced by a fixed ring 13preventing the dropping of the jaws out of the socket. The ring 13 isfixed to the pin 5 by means of screws 16. The shell 12 has circularrecesses 14: and 15 in its ends, the recess 14 being engaged. by aflange on the part 1, and the recess 15 by the ring 18, so as to preventaxial displacement of the shell. It is also provided with an innerflange 17 having radial slots in which the pins 10 of the jaws 4 areguided. The flange 17 can be replaced either by a'ring wedged into theshell 12, or by means of forks or double pins fixed to said shell or byany other suitable means. Of course the pins and slots can be exchangedwith each other so that the shell carries the pins and the jaws have theslots.

In the construction shown in Figs. 3 and L drills can be exchangedwithout stopping the engine driving the drill socket.

I claim 1. A drill socket comprising two rotatably connected members,one member having an internal cylindrical surface, longitudinallydisposed pins connected to the other member and projected through theinterior of the first member, tapped gripping jaws, having an allthrough uniform cross-section, mounted on said pins so as to have acertain amount of free play, means for causing the jaws to roll on saidcylindrical surface so as to increase and diinin- .ish the space betweenthe gripping surfaces when the members are rotatably displaced, andmeans for holding the jaws normally in closed position, substantially asset forth.

E1 drill socket comprising a head, a loose shell rotatably fitted withone end on a flange of the same, longitudinally disposed pins connectedto the head and pro ected through the interior of the shell, a ringconnecting" the ou'ier ends of the pins and guide' the outer end of theshell, tapped gripn. amount of free play and so 0 bear against thecylindrical surface l ll "when gripping, an interior lial slots in theshell, studs on the gripping jaws engaging said slots so as to cause thejaws to roll on the cylindrical surface of the shell for increasing anddiminishing the space between the gripping surfaces when the shell isrotated on the head, and a spiral spring connected with one end to theshell and with the other end to the head so as to hold the jaws normallyin closed position, substantially as set forth. In testimony whereof Ihave hereunto signed my name this 11th day of May 1910, in the presenceof two subscribing witnesses.

PER GOTTHARD BLOMBERG. Witnesses NORVALD NYSTROM, Hnowlo MELINDER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

